ZKBS recommendation for risk assessment of naked naive viruses

In 2017, a total of 13 new viral genomes were discovered in the genome sequences of various fish species. The genomes of the fish viruses show great similarity to the enveloped hepatitis B virus from risk group 2, but do not contain any envelope protein genes. Due to the envelope proteins, hepadnaviruses are adapted to a very narrow host range, whereas nakednaviruses have a significantly broader host spectrum. Outside of the currently known fish species, the distribution of nakednaviruses in other vertebrates has not yet been described. Likewise, no information on transmission is known, and no cases of disease in bony fish have been attributed to these viruses. The Central Commission for Biological Safety (ZKBS) therefore recommends classifying nakednaviruses as donor and recipient organisms for genetic engineering work in risk group 1. This assessment is justified by the described narrow host range, the unknown pathogenicity, and the previously unrecorded transmission to other organisms. The full statement from the ZKBS can be found here.